1. Field of the Invention
The present invention relates to a surface-mount device, and more particularly to a miniaturized surface-mount device formed as a single-piece electronic device to provide multiple functions, and a process for producing such a surface-mount device containing neither conventional lead frame nor external pins.
2. Description of Related Art
In present process for making packages of semiconductor dies, lead frames are a key component for success of resultant packages. For packaging semiconductors to possess different types or functions or for different applications, there are various forms of lead frames have been designed and developed until now.
With the trend of microminiaturization in IC processing, electronic devices used in modern compact consumer electronics are increasingly miniaturized. For example, in order to meet the miniaturization, surface-mount devices (hereinafter referred to as SMDs) provided with more compact size are suitably developed for use in connection to printed circuit boards (PCBs).
However, as far as known existing lead-frame-based packaging is concerned, when applied to such miniaturized SMDs, it is likely that a miniaturized diode die cannot be installed on a lead frame accurately. Therefore, a miniaturized SMD if poorly installed may cause the resultant package functionally inferior, or even inactive. Thus, the known existing lead-frame-based packaging is not suitably applicable to packaging miniaturized SMDs.
Another recent trend is that integrating devices with different functions are allowed to be wholly packaged into a single-piece SMD through multilayer technology. For example, an inductor and a capacitor are combined into a single-piece SMD to form an inductor-capacitor filter (also referred to as a LC filter) that has filtering function. Alternatively, a resistor and a capacitor may be combined into a single-piece SMD to form a resistance-capacitance filter (also referred to as a RC filter) that also has filtering function.
However, such a single-piece SMD made of two functionally different devices through multilayer technology tends to have the devices combined loosely, separating from each other, and becoming invalid because the two devices usually have different sintering temperatures and contraction coefficients.